안녕하세요. 다음주 월요일(10월 13일)에 세미나가 개최됩니다. 이번 세미나는 1층 330126호에서 진행됩니다. 많은 참석 부탁드립니다.감사합니다. ========================= 제 목 : Three-Membered Rings and Triple Bonds as Ideal Starting Materials for Domino Cascades 연 사 : Prof. Daniel B. Werz (Institute of Organic Chemistry, Department of Life Sciences, Technische Universität Braunschweig) 일 시 : 2014년 10월 13일 (월) 오후 4시 30분 장 소 : 화학관 1층 첨단강의실 (330126호실) ------------------------- Three-Membered Rings and Triple Bonds as Ideal Starting Materials for Domino Cascades Cyclopropanes as well as carbon-carbon triple bonds are systems being high in energy. Therefore, both moieties are ideally suited for a cascade of consecutive reactions (domino reactions). In a first part, domino reactions based on ring-enlargement reactions of donor-acceptor-substituted cyclopropanes are discussed. Aldehyde, ketimines and thioketones are utilized as acceptors whereas ether moieties serve as donor.A rearrangement leads to the respective five-membered rings which tend to eliminate water. As a result, aromatic systems are formed.Depending on the substrate domino cascades are initiated which are able to transform the biscyclopropane derivative 1 in one step into the corresponding quaterpyrrol 2. In a second part, Pd-catalyzed domino reactions starting with triple bonds attached to carbohydrate derivatives 4 are reported to construct a variety of chroman- and isochroman-type structures such as 5. Such domino sequences are also employed to a variety of other processes leading to complex scaffolds in a facile and efficient fashion. References  H.-U. Reißig, R. Zimmer, Chem. Rev. 2003, 103, 1151-1196.  a) T. F. Schneider, J. Kaschel, B. Dittrich, D. B. Werz, Org. Lett. 2009, 11, 2317-2320; b) T. F. Schneider, J. Kaschel, S. I. Awan, B. Dittrich, D. B. Werz, Chem. Eur. J. 2010, 16, 11276-11288; c) J. Kaschel, T. F. Schneider, D. Kratzert, D. Stalke, D. B. Werz, Angew. Chem. Int. Ed. 2012, 51, 11153-11156. d) J. Kaschel, C. D. Schmidt, M. Mumby, D. Kratzert, D. Stalke, D. B. Werz, Chem. Commun. 2013, 49, 4403-4405.  a) M. Leibeling, D. C. Koester, M. Pawliczek, S. C. Schild, D. B. Werz, Nature Chem. Biol. 2010,6, 199-201; b) M. Leibeling, B. Milde, D. Kratzert, D. Stalke, D. B. Werz, Chem. Eur. J. 2011, 17, 9888-9892; c) M. Leibeling, D. B. Werz, Chem. Eur. J. 2012, 18, 6138-6141; d) M. Leibeling, M. Pawliczek, D. Kratzert, D. Stalke, D. B. Werz, Org. Lett. 2012, 14, 346-349.
이번주 금요일(9월 26일)에 세미나가 개최됩니다. 많은 참석 부탁드립니다.감사합니다. ========================= 제 목 : Process Development of PI3Kβ-Sparing Inhibitor GDC-0032(Taselisib) 연 사 : TRAVIS P. REMARCHUK, PH.D.(Genentech Inc, Small Molecule Process Chemistry) 일 시 : 2014년 9월 26일 (금) 오후 4시 30분 장 소 : 화학관 1층 첨단강의실 (330126호실) ------------------------- Process Development of PI3Kβ-Sparing Inhibitor GDC-0032(Taselisib) Genentech Inc, Small Molecule Process Chemistry1 DNA Way, South San Francisco, CA 94080, USA Abstract: GDC-0032 is an orally dministrated potent PI3K kinase inhibitor that was discovered at Genentech and currently in PhI clinical trials for the treatment of cancer. In this presentation, the evolution of the process chemistry from the medicinal chemistry route up to the current manufacturing route used to produce GDC-0032 on multikilogram scale will be discussed. Multiple routes to the key starting materials as well as a more efficient convergent end-game synthesis to the API will be highlighted.
9월 11일 목요일에 세미나가 개최됩니다. 많은 참석 부탁드립니다.감사합니다. ========================= 제 목 : Nanostructured Thermoelectric Materials 연 사 : Prof.HNG Huey Hoon(Nanyang Technological University) 일 시 : 2014년 9월 11일 (목) 오후 4시 30분 장 소 : 화학관 세미나실 (330226호실) ------------------------- Nanostructured Thermoelectric Materials It is known that of all the primary energy we harness and use, only 30% is translated into useful work. A staggering 70% is wasted as dissipated heat during energy conversion, transportation and storage. This huge loss is itself a source of recyclable energy. If the waste heat leakage can be minimized by having the heat harnessed, stored and reused, the additional available energy can be huge. Thermoelectric (TE) devices, which can directly convert heat into electricity or vice versa, could play an important role in the energy market. TE devices can be potentially used as power generators, heat pumps, coolers and thermal sensors, which make them a unique energy harvesting and heat management system. For example, in Singapore, 42% of residential electricity is used for cooling (air conditioners), which are expected to grow at least 10% per year over the next decades. This percentage would be dramatically decreased if high-efficiency TE devices are developed to replace the traditional cooling system and realize the on-demand cooling in our daily lives (i.e. in the case of residential cooling, we can choose to only cool the chair or bed instead of the whole room). Till now, TE technology is too inefficient to be cost-effective for practical applications. Nevertheless, modern synthesis and characterization technologies are bringing TE research into a new era. In fact, the TE research area has become more promising and exciting in recent years as seen from the market forecasts for TE energy harvesters, and many companies such as BMW, have invested in TE technology. One of our research focuses is use nanostructuring to improve the TE performance of both conventional and new materials, which allows further optimization and scaling to broaden the application of TE devices. In this talk, I will focus on the various nanostructuring approaches that our group in MSE/NTU has considered to improve the performance and efficiency of various TE materials systems. I was also report on the feasibility of fabricating thin film TE device using inkjet printing, which opens up the possibility of low cost manufacturing opportunity.
다음주 목요일(8월 14일)에 특별세미나가 개최됩니다.
많은 참석 부탁드립니다.감사합니다.
제 목 : PERFORMANCE OF AMINE-RICH PLASMA POLYMERS IN BIOSENSING AND TISSUE ENGINEERING
연 사 : Prof. Lenka Zajickova(Central European Institute of Technology - CEITEC, Masaryk University, Brno, Czech Republic/Faculty of Science, Masaryk University, Brno, Czech Republic)
일 시 : 2014년 8월 14일 (목) 오후 4시 30분
장 소 : 화학관 세미나실 (330226호실)
pERFORMANCE OF AMINE-RICH PLASMA POLYMERS IN BIOSENSING AND TISSUE ENGINEERING
Lenka Zajíčková1,2, Anton Manakhov1, Marek Eliáš1,2, Petr Skládal1,2, David Nečas1,2,
Jan Čechal3, Josef Polčák3
1 Central European Institute of Technology - CEITEC, Masaryk University, Brno, Czech Republic
2 Faculty of Science, Masaryk University, Brno, Czech Republic
3 Central European Institute of Technology - CEITEC, Brno University of Technology, Brno, Czech Republic
The bio-applications of amine thin films, such as a biomolecule immobilization, biosensors or a cell adhesion enhancement require good layer stability in water. However, an improved film stability achieved by increased polymer cross-linking results in lower density of amine groups for typical allylamine or ammonia/ethylene plasma polymerization process. Cyclopropylamine (CPA) is a promising non-toxic monomer recently used for the deposition of amine-rich thin films. A relatively good water stability reported for CPA plasma polymers was promising for the bio-applications but these studies were not carried out so far.
In this work, the electrospun polycaprolactone (PCL) micro/nanofibers with the mean thickness of 1.2 ± 0.4 µm and a pore size of 8 ± 2 µm and cell cultivation dishes were coated by amine-rich thin films using low pressure capacitively coupled plasma polymerization of CPA in continuous wave and pulsed mode. In pulsed discharges the film exhibited 7 at.% of amine groups and only 1 % of the thickness was lost after immersion of in water for 216 hours. The deposition of this coating improved the cell adhesion and proliferation, as the number of mouse myoblasts grown on the substrate surface during 1 day of cultivation increased by a factor of five after deposition of CPA plasma polymer compared to the uncoated substrate.
Additionally, CPA plasma polymerization was employed to deposit stable amine thin films on the surface of quartz crystal microbalance (QCM) biosensors. The antibody specific to human serum albumin (anti-HSA) was attached to the QCM surface via cross-linkage obtained by intermediate reaction with glutaraldehyde. All steps of the bio-immobilization were studied by X-ray photoelectron and infrared spectroscopy to characterize surface and layer chemistry. The immunosensor specificity towards the HSA antigen was confirmed by the flow test for three QCM sensors which preparation started with CPA plasma polymers of different thicknesses: 20, 100 and 350 nm. The strongest response to the HSA antigen was observed for the thinnest CPA plasma polymer film and the sensor sensitivity was in this case better than for the previously reported QCM sensors functionalized by the thiol-based self-assembled monolayer.
이번주 목요일(7월 24일)에 특별세미나가 개최됩니다. 많은 참석 부탁드립니다.감사합니다. ========================= 제 목 : Organocascade reactions and synergistic c atalysis: two open gates for the synthesis of complex scaffolds 연 사 : Prof. Ramon Rios(University of Southampton, UK) 일 시 : 2014년 7월 24일 (목) 오후 4시 30분 장 소 : 화학관 세미나실 (330226호실) ------------------------- Organocascade reactions and synergistic c atalysis : two open gates for the synthesis of complex scaffolds Prof. Ramon Rios University of Southampton, UK Abstract: The synthesis of complex scaffolds is one of the major goals for synthetic chemists. In our research group we are working in the development of new organocascade reactions and in synergistic catalysis to afford new 3D-scaffolds. Several organocascade reactions have been developed in our research group to synthesize valuable compounds in high yields and ee, on the other hand Synergistic catalysis, in which two catalytic cycles involving two separate catalysts work in concerted fashion to create a single new bond, has emerged as a powerful approach for the development of new reactions. Here in we will report our last efforts in this fields.
이번주 목요일(6월 26일)에 세미나가 개최됩니다. 많은 참석 부탁드립니다.감사합니다. ========================= 제 목 : Out-of-equilibrium materials constructed from molecular switches and superparamagnetic nanoparticles 연 사 :Dr. Rafal Klajn(Department of Organic Chemistry Weizmann Institute of Science,Israel) 일 시 : 2014년 6월 26일 (목) 오후 2시 장 소 : 화학관 세미나실 (330226호실) ------------------------- Title: Out-of-equilibrium materials constructed from molecular switches and superparamagnetic nanoparticles Dr. Rafal Klajn (Department of Organic Chemistry Weizmann Institute of Science,Israel) Abstract: Living organisms are the most prominent examples of systems self-assembled under far-from-equilibrium conditions. Inspired by Nature, we design new materials that are capable of existing only as long as an external source of energy is supplied. In this talk I will introduce molecular switches and superparamagnetic nano-particles as the key building blocks of dynamically self-assembling materials. These new materials enable applications as diverse as light-controlled catalysis or manipulating non-magnetic objects with the help of magnets.
[세미나 공지] - 2014년 6월 20일(금) ========================= 제 목 : Interfacial interactions in surface chemistry 연 사 : Dr.JUNG, Jaehoon(RIKEN Advanced Science Institute, Hirosawa) 일 시 : 2014년 6월 20일 (금) 오후 4시 30분 장 소 : 화학관 세미나실 (330226호실) ------------------------- Interfacial interactions in surface chemistry JUNG, Jaehoon RIKEN Advanced Science Institute, Hirosawa 2-1, Wako-shi, Saitama 351-0198, Japan e-mail: firstname.lastname@example.org Interfacial interaction has long served as a key element to get fundamental insights into surface science and related chemical phenomena. Understanding interfacial interaction is, therefore, of great importance to achieve robust predictability and high controllability in a variety of applications. Herein, we discuss the role of interfacial interaction in (i) fabricating a well-ordered molecular superstructure on metal surface, (ii) controlling chemical reactivity of ultrathin oxide film grown metal substrate, and (iii) introducing a novel functional group to the basal plane of graphene grown on metal substrate. Computational study based on density functional theory (DFT), in close conjunction with scanning tunneling microscopy (STM) experiment at atomic spatial resolution, has been mainly performed to unveil the influence of a broad range of interfacial interactions on geometric and electronic features of various surface species. Firstly, we successfully achieved a two-dimensional molecular superstructure of a fluorinated fullerene (C60F36) on Au(111) in a highly ordered manner. In STM experiment, we observed that the molecules in the well-ordered region are composed of only theC3 isomer, despite the existence of three isomers (C3,C1, and T). The DFT results revealed that the adsorption and lateral orientations of individual C60F36molecules in the superstructure are determined by the localized distribution of LUMO and by intermolecular electrostatic interactions, respectively. We expect that such well-ordered molecular film with high electron affinity might be useful to achieve a uniformn-type semiconducting molecular component in organic electronic device. Secondly, we demonstrated that the chemical reactivity for water dissociation on an ultrathin MgO film grown on Ag(100) substrate depends greatly on film thickness and is enhanced as compared to that achieved with their bulk counterpart. The change in the chemical reactivity of ultrathin MgO film depending on the film thickness can be explained by the interaction strength between the oxide and metal interface layers. Therefore, the manipulation of the local structure at the oxide-metal interface plays a pivotal role in controlling the chemical reactivity of ultrathin oxide film.[3a] We have recently presented that the chemical reactivity of MgO/Ag(100) for the dissociation of individual water molecules can be systematically controlled by interface dopants over the film thickness.[3b]We introduced the 3d transition metal dopants (Sc ~ Zn) into the oxide-metal interface due to the high tunability with a number of d electrons. DFT calculations revealed that the adhesion at the oxide-metal interface can be addressed by the interaction between a dopant and the oxide layer with aid of ligand field theory and is linearly correlated with the chemical reactivity of the oxide film. Our study provides not only profound insight into the chemical reactivity control of ultrathin oxide film but also an impetus for investigating ultrathin oxide ﬁlms for a wider range of applications. Lastly, we suggest, for the first time, that the atomic oxidation of graphene grown on a metal substrate results in the formation of graphene enolate, i.e., negatively charged oxygen adsorbed at ontop position on its basal plane, which is strikingly different from the formation of epoxy groups, i.e., adsorption of atomic oxygen at bridge position, on free-standing graphene and on graphite. Whereas the enolate is the transition state between two nearest epoxides both on graphene and on graphite, we revealed that improved interfacial interaction between graphene and metal substrate during atomic oxidation plays a crucial role not only in the formation of graphene enolate as a local minimum but also in stabilizing it over the graphene epoxide. To conclude, our studies open up a new vista for the design of novel materials of new potentials with desired functions based on the deep insight into the a wide range of interfacial interactions and its fine control. T. K. Shimizu§, J. Jung§, T. Otani, Y.-K. Han, M. Kawai, and Y. Kim, ACS Nano 6, 2679 (2012). [§equally contributed]. (a) H.-J. Shin, J. Jung, K. Motobayashi, S. Yanagisawa, Y. Morikawa, Y. Kim, and M. Kawai, Nat. Mater. 9, 442 (2010); (b) J. Jung, H.-J. Shin, Y. Kim, and M. Kawai, Phys. Rev. B 82, 085413 (2010). (a) J. Jung, H.-J. Shin, Y. Kim, and M. Kawai, J. Am. Chem. Soc. 133, 6142 (2011); (b) J. Jung, H.-J. Shin, Y. Kim, and M. Kawai,J. Am. Chem. Soc. 134, 10554 (2012). J. Jung, H. Lim, J. Oh, and Y. Kim, J. Am. Chem. Soc.submitted (2014).
이번주 목요일(6월 5일)에 세미나가 개최됩니다. 많은 참석 부탁드립니다.감사합니다. ========================= 제 목 : Moving Photodynamic Action into the 21st Century 연 사 : prof. Engin Umut Akkaya(Bilkent University) 일 시 : 2014년 6월 5일 (목) 오후 4시 30분 장 소 : 화학관 세미나실 (330226호실) ------------------------- Moving Photodynamic Action into the 21st Century Engin U. Akkaya* email@example.com Department of Chemistry and UNAM-National Nanotechnology Research Center, Bilkent University, 06800 Ankara, Turkey. Our research group has contributed to the development of molecular logic gates over the years. However in recent years, the need to move molecular logic from the realm of intellectual exercise to practicality became an urgent matter. We, among a few others are convinced that the first unequivocal application will present itself in the nanomedicine field. One particular field of inquiry which could benefit from such fusion of ideas is photodynamic therapy. Photodynamic therapy (PDT) is a noninvasive method of treating malignant tumors and age-related macular degeneration, and is particularly promising in the treatment of multidrug-resistant tumors. The PDT strategy is based on the preferential localization of certain photosensitizers in tumor tissues upon systemic administration. The sensitizer is then excited with red or near infrared (NIR) light, generating singlet oxygen (1O2) and thus irreversibly damaging tumor cells. Current practice of PDT is limited to a few functionalized porphyrins and related compounds, however these are not considered to be ideal photosensitizers for use in PDT. Among the limitations, the most prominent is the low extinction coefficient of porphyrins in the body’s therapeutic window (650–800 nm).. As a consequence, many research groups worldwide are engaged in efforts to develop better sensitizers. One important aspect is the tight control of the delivery of cytotoxic singlet oxygen to be produced. In an earlier design, we proposed a sensitizer which behaves as an “AND” logic gate. Later, we proposed a demultiplexer design which can switch from therapeutic to diagnostic mode autonomously. The other path we are following is trying to find alternative excitation protocols for photodynamic action. The methodologies which we are currently evaluating are, chemiluminescence, persistent luminescence, and direct production of singlet oxygen. Our recent progress in these fields of research will be presented. References \'Selective Manipulation of ICT and PET Processes in Styryl-Bodipy Derivatives: Applications in Molecular Logic and Fluorescence Sensing of Metal Ions\' Ö. A. Bozdemir, et al., J. Am. Chem. Soc., 2010,132, 8029-8036. \'From Virtual to Physical: Integration of Chemical Logic Gates\' R. Guliyev, Ş . Öztürk, Z. Köstereli, E. U. Akkaya, Angew. Chem. Int. Ed., 2011, 50, 9826-9831. \'Designing Excited States: Theory-Guided Access to Efficient Photosensitizers for Photodynamic Action\' Y. Çakmak, et al., Angew. Chem. Int. Ed., 2011,50, 11937-11941. \'Cascading of Molecular Logic Gates for Advanced Functions: A Self-Reporting, Activatable Photosensitizer\' Erbas-Cakmak, S.; Akkaya, E. U., Angew. Chem. Int. Ed.2013, 52, 11364.
이번주 목요일(4월10일)에 세미나가 개최됩니다.
많은 참석 부탁드립니다.감사합니다.
제 목 : NOx storage-reduction (NSR) catalysts for diesel emissions control:
Toward the understanding of sulfur poisoning mechanism
연 사 : 김도희 교수(서울대학교)
일 시 : 2014년 4월 10일(목) 오후 4시 30분
장 소 : 화학관 세미나실 (330226호실)
NOx storage-reduction (NSR) catalysts for diesel emissions control:
Toward the understanding of sulfur poisoning mechanism
이번주 목요일(4월3일)에 세미나가 개최됩니다. 많은 참석 부탁드립니다.감사합니다. ========================= 제 목 : The Excited-States Dynamics of Single-Walled Carbon Nanotubes Wrapped by Ionic Conjugated Polymers 연 사 : 박재홍 교수(National Renewable Energy Laboratory (NREL), Chemical and Materials Science Center) 일 시 : 2014년 4월 3일(목) 오후 4시 30분 장 소 : 화학관 세미나실 (330226호실) ------------------------- The Excited-States Dynamics of Single-Walled Carbon Nanotubes Wrapped by Ionic Conjugated Polymers Park, Jaehong National Renewable Energy Laboratory (NREL), Chemical and Materials Science Center Rationally designed, highly charged polymers are used to effectively wrap and disperse single-walled carbon nanotubes (SWNTs) in solution. When applied to samples of SWNTs that are enriched in a single chirality, the resulting polymer-wrapped SWNT hybrids are used to investigate previously unidentified carbon nanotube excited states and the potential of these supramolecular assemblies for light-to-fuel energy conversion reactions. Highlights include femtosecond pump-probe transient absorption spectroscopic experiments that identify, for the first time, microsecond-lived SWNT intrinsic excited-state as a function of local dielectric environment and dispersing agents, and demonstrate photoinduced electron transfer dynamics between a SWNT and a semiconducting polymer where we fully characterize the charge-separated products, and the dynamics of charge separation and recombination.